This application relates to a modular test instrument, wherein a base unit providing certain non-application-specific functions is specialized for a particular application by assembly thereto of an application module.
With the proliferation of a wide variety of microprocessorxe2x80x94and computer-controlled equipment there has arisen a need for correspondingly complex test and diagnostic equipment. More specifically, equipment from appliances to automobiles, elevators to automatic teller machines, building HVAC equipment to gasoline pumps, and of course a wide variety of computer and communication equipment per se, is now provided with unprecedented functionality through extensive use of complex electronics, particularly microprocessors. Testing such complex equipment requires correspondingly sophisticated test equipment.
While the specific test methodology to be employed varies widely, in general a test instrument specialized to the equipment to be tested is connected thereto by way of a physical interface, such that a microprocessor of the test instrument is in signal-communicating relation to the circuitry of the equipment. Appropriate test conditions are then createdxe2x80x94for example, in testing an automatic teller machine, the test technician might simulate a particular type of transactionxe2x80x94and the test instrument will monitor the response of the equipment. In the telecommunication connection, the testing may involve monitoring ongoing traffic; injection of predetermined test messages, to monitor the system""s response; measuring operational parameters, such as bit error rates, message travel times and the like; or monitoring the operation of individual components of the system.
As noted, as a rule the test instrument employed for testing given equipment is specialized thereto, that is, is useful only for testing a specific type of equipment or perhaps a class of related equipment. Automobile manufacturers, for example, provide their dealers and authorized repair shops with new computers for testing and diagnosing the engine management systems of each new class of cars, i.e., as the electronics of each new generation of cars become more sophisticated, the dealers must upgrade their computers accordingly. Moreover, each manufacturer employs a unique format not only for the physical interface, but also for the data formats used, the microprocessor architecture, and so on, so that each instrument is usable only with a single manufacturer""s vehicles.
In general, such test instruments comprise a user interface for communicating information to and receiving instructions from the technician. Information is usually communicated to the user by way of a display screen; input may be accommodated by way of a keyboard or keypad, by the user""s scrolling along a list of possible choices, by pointing to a specific region on a graphical user interface (GUI) with a xe2x80x9cmousexe2x80x9d, xe2x80x9ctrackballxe2x80x9d, or other pointing device, or, if the display is touch-sensitive, by simply contacting the defined regions. In most cases, the user interface is designed to xe2x80x9cpromptxe2x80x9d the user through an appropriate 30 sequence of xe2x80x9cscreensxe2x80x9d so as to select a particular test to be performed, determine various parameters, control the disposition of the results, and the like.
It has not escaped the attention of the art that despite their wide variety, most such test instruments have many common physical features, and that they differ principally in the physical interface used to make the connection to the equipment under test and in the software required to perform the test and to define the user interface. In particular, the art has recognized that substantial savings could be realized if a common unit, including generic components such as a display screen, power supply, and user input interface, could be xe2x80x9ccustomizedxe2x80x9d for a particular application by addition thereto of physical interface hardware and internal and user interface software.
For example, a number of devices have been offered for telecommunications testing wherein a basic unit is xe2x80x9ccustomizedxe2x80x9d for testing devices obeying varying protocols. Here the basic units have typically been xe2x80x9claptopxe2x80x9d personal computers adapted for testing of particular devices by plug-in memory cards and/or supply of floppy disks providing the corresponding software. Such plug-in cards are normally rather delicate, and the floppy disks are susceptible of loss or physical damage. See generally U.S. Pat. No. 5,121,342 to Symborski; Schillaci et al U.S. Pat. No. 5,583,912; Horton et al U.S. Pat. No. 5,533,093; Selig et al U.S. Pat. No. 5,521,958; and Heins U.S. Pat. No. 5,528,660.
U.S. Pat. Nos. 5,432,705 and 5,511,108, both to Severt et al, show an xe2x80x9cadministrative computerxe2x80x9d for storing work order information, customer addresses and the like, and which can be coupled to test equipment for recording test results. In a second embodiment of this device, shown in the ""108 patent, the administrative computer is divided into two mating portions 402 and 404 and a xe2x80x9cslicexe2x80x9d 438 can be inserted and assembled therebetween. See FIGS. 12, 13, and 24 of the ""108 patent, and the specification at cols. 9-12. As discussed at col. 9, line 45, the slice xe2x80x9ccontains circuitry and devices to facilitate testing, maintaining or installing telephone lines or equipment.xe2x80x9d The slice includes the physical connection to the circuit to be tested; see FIG. 18 and the specification at col. 11, lines 1-5.
The ""108 patent states explictly that other types of slice could be provided for testing equipment other than telephone equipment per se, such as xe2x80x9cfiber optic systems, . . . non-telephone communications systems . . . for supporting general field servicing of electrical devices, e.g., copiers, printers, computers, faxes and the like . . . Although only one slice is provided in the depicted embodiment, it is possible to configure a computer to accomodate more than one slice, to provide a plurality of capabilities . . . Slices can also be provided which enhance the capabilities of the basic computer . . . such as . . . additional memory, co-processing capabilities, networking capabilities or the like.xe2x80x9d Col. 23, lines 39-56.
The device shown in the ""108 Severt et al patent is essentially a complete computer that can be adapted for any of a variety of specific uses by assembly of a particular slice. This is evidently not intended to be performed repetitively; note the complicated assembly arrangements shown by FIG. 24. It is therefore clear when the slice has been assembled, the unit has essentially been dedicated to the particular use. This significantly limits the utility of the device; for example, there are numerous occasions in the telecommunication industry at which two different types of communications systems meet, as where a satellite xe2x80x9cdownlinkxe2x80x9d is interfaced to a land line. It would be highly desirable to provide a technician with a single instrument capable of ready and convenient adaptation to testing both types of equipment.
Other generally relevant patents can be summarized as follows:
Debacker U.S. Pat. No. 5,608,644 shows a simulator and method for testing system software of a communication system. The software employed is divided into xe2x80x9cprogram modulesxe2x80x9d for testing various system functions.
Dariano U.S. Pat. No. 5,173,896 shows a T-Carrier Network Simulator for training technicians by simulating various network faults. It appears that various faults are simulated by plugging xe2x80x9csmart jacksxe2x80x9d emulating various circuit characteristics into the simulator.
Butler et al U.S. Pat. No. 5,377,259 shows a data terminal for field use by technicians capable of downloading software, work orders, and the like from a host computer over a normal telephone line. Various communication protocols are stored by the unit. Additional Butler U.S. Pat. Nos. 4,837,811 and 4,922,515 are generally similar.
Dack et al U.S. Pat. No. 4,996,695 shows a test device for testing circuits in which a shift register is provided to compensate for delays introduced in testing.
Fitch U.S. Pat. No. 5,557,539 shows an instrument for testing voice mail systems. A memory stores a number of test procedures.
Jablway et al U.S. Pat. No. 4,536,703 shows test instruments for detecting shorts and opens in multiple wire sets. Two instruments at spaced locations may be used simultaneously.
Harris et al U.S. Pat. No. 3,956,601 shows use of paired telecommunications analyzers at opposite ends of a connection. One inserts a predetermined test signal, and the other detects the signal.
It is therefore an object of the invention to provide an improved modular test instrument, wherein a base unit comprising certain generic components and software can be adapted to performance of any of a variety of applications upon assembly thereto of a corresponding application module.
It is a further object of the invention to provide such a modular test instrument wherein the application modules can be readily and conveniently interchanged, to provide increased versatility in use.
It is a further object of the invention to provide a modular test instrument that does not require use of floppy disks, plugin memory or other cards, or other additional equipment, to perform useful test functions, in order to simplify the design, construction, and, in particular, the operation of the instrument.
A further object of the invention is to provide such a modular test instrument wherein each application module includes application-specific program data and software, so that an application-specific user interface is displayed by the base unit upon assembly of the application module to the base unit.
A further object of the invention is to provide new methods of performing testing of sophisticated equipment using instruments comprising a generic base unit specialized to the task by assembly of a corresponding application module.
1. Definitions and Examples of Terminology
The following definitions and examples of terminology used herein, which are to be considered inclusive and non-limiting, are provided to simplify the reader""s understanding of the invention and its relation to the prior art discussed.
The present invention relates to application-specific instruments or computers for performing certain end-user functions in the context of certain applications. In the particular embodiment described in detail below, the instrument is a test instrument for testing telecommunications apparatus, communications facilities, and systems. The application is then telecommunications testing, while the end-user functions are specific tests or operations to be performed, e.g., monitoring communications on a given channel, inserting test messages to monitor the accuracy of their transmission, measuring the time of transmission of a message, or the like.
The instrument is amenable to performance of various applications, such as testing or monitoring telecommunication equipment or systems, as above, but also for testing various other classes of devices, such as automatic teller machines, electronically-controlled gasoline pumps, electronic security equipment, automotive engine management systems, credit card verification equipment, various kinds of computer equipment and peripherals, computer-controlled drafting, construction, fabricating, and assembly equipment, domestic and commercial appliances, and many additional types of device amenable to testing or diagnostic procedures for verifying proper operation of electronic circuit components and accompanying software, and where appropriate, verification of the operation of associated mechanical components.
In each case, the intent of the invention is to provide an integrated instrument for electrical connection through an application-specific physical interface to the equipment, system, or device being tested or monitored. The instrument comprises an application-specific user interface for guiding a technician or other user in properly performing the test. Typically the user interface of the instrument will include a touch-sensitive display for both prompting the user to select a test to be performed and to allow the user to input various data items required, as well as displaying the test results; however, the same functions could be provided by a display screen and a separate user input device, such as a keyboard or keypad, or a mouse, trackball, or other pointing device.
In order that common components can be used to perform a number of different applications, the instrument comprises a non-application-specific base unit comprising the user interface, again typically a touch-screen display for displaying information, prompting the user, and accepting user input. The base unit also comprises non-application-specific software for operating the display and accepting user input, a power supply, external communication devices, and other software and equipment for non-application-specific functions. The base unit is not itself capable of carrying out any end-user functions, though it can be capable of certain other non-application-specific functions, such as receiving upgraded software, downloading archival data having been copied from a particular device during testing, or the like.
The base unit is specialized, that is, becomes part of an application-specific instrument, when it is combined with an application module. Each application module mates physically with the base unit to form an integrated test instrument; signal-communicating connections between the base unit and application module are made simultaneously upon their assembly. Each application module is specific to a given application supporting a number of related end-user functions. For example, if the application is telecommunications testing, the end-user functions may include monitoring particular communications for accuracy, monitoring round-trip travel time of messages between specified points in the system, measuring bit-error rates, and the like. Differing application modules are provided for testing telecommunication systems or equipment obeying different communication protocols, whereby the bit rates, logic levels, and like standards provided by the physical interface of each application module vary in accordance with the specific system or equipment involved.
In order to most conveniently prompt the user to select appropriate end-user functions, define appropriate tests, and the like, each application module stores application-specific program data and software cooperating with the non-application-specific, generic software and equipment of the base unit to support the various application-specific end-user functions appropriate to the application to be supported. The application-specific program data and software will typically include application-specific user interface software cooperating with the generic user interface software stored by the base unit to provide an application-specific user interface, that is, a user interface prompting the user for data and selections appropriate to the specific device or system under test.
Preferably, the combination of the base unit and application module comprises sophisticated software and sufficient processing power to define a graphical user interface (GUI). GUI software defines regions on the display screen whereby the user is prompted to make various selections, provide required input data and the like by indicating corresponding areas of the screen (as opposed to less sophisticated user interfaces, e.g., wherein the user makes selections by xe2x80x9cscrollingxe2x80x9d through lists of possible selections). As implemented herein, each application module stores software defining an application-specific graphical user interface (ASGUI), comprising a sequence of screens through which the user is prompted to select an end-user function to be performed, input data needed to perform the end-user function, control the disposition of the result, and the like. Where the display device is a touch-sensitive display screen, the ASGUI allows user input by contact of the defined regions of the screen. Otherwise a mouse or other xe2x80x9cpointingxe2x80x9d device is used to select the appropriate screen regions defined by the ASGUI.
The end-user functions supported by a given application module include a wide variety of tests, monitoring procedures, downloading of archival data stored by the equipment under test, and the like, varying widely with the particular equipment. For If example, in testing of automatic teller equipment, the instrument may perform various simulated transactions to verify proper operation, and may also download and store archival transaction information, for cross-correlation to similar information stored at a central site. Security equipment, such as keycard-controlled locks, may similarly be tested by introduction of a test key to verify proper detection and processing operation; the instrument may also allow downloading of stored access histories. End-user functions performed with respect to telecommunication equipment may involve monitoring ongoing communications, error rate measurement, injection of faulty or diagnostic messages into a stream of user messages to observe their disposition by the system, and numerous other options.
In each case, the application module comprises a suitable application-specific physical interface for making appropriate connection to the circuitry of the system or equipment under test, and application-specific circuitry and software as needed. In the telecommunications testing application, the application-specific physical interface may comprise ports for jumper wires making connection to test points provided on conventional equipment, or an antenna and suitable transceiving circuitry for connection to wireless equipment, e.g., cellular telephone equipment.
Other applications will necessitate different physical interfaces, of course; in the context of testing automotive engine management systems, the application module will typically include a cable to be plugged into a multipin receptacle connected to the engine management computer. In verifying the operation of credit-card verification equipment normally connected to a remote computer by the telephone system, the application module may include a credit-card-shaped test object having known codes stored thereon, and male and female telephone connectors allowing the instrument to conveniently be interposed between the device to be tested and the telephone line.
The application-specific program data and software stored by each application module similarly includes all information for carrying out the end-user functions relevant to the corresponding application, in addition to the information necessary to support the ASGUI. For example, an application module for testing of telecommunications apparatus, communications facilities or systems operations obeying the so-called xe2x80x9cT1xe2x80x9d protocol (this referring to an international standard governing such physical parameters as message format, xe2x80x9chighxe2x80x9d and xe2x80x9clowxe2x80x9d bit levels, permissible distortion of pulse shape and timing during transmission, and the like) will store the corresponding functional information needed to perform suitable tests.
Similarly, the application-specific circuitry and software in the context of testing communications equipment includes components to generate pulses conforming to the communication protocol, software to assemble such pulses into suitable test messages, timing circuitry to measure time delays experienced by particular test messages, error detection circuitry for monitoring the integrity of test messages, and the like.
The application-specific program data and software may also include libraries of stored tests, i.e., collections of parameters of commonly-performed tests, so that the user may simply choose a test from the library, rather than specify each parameter separately, and may include previously-stored archival and status data, information correlating specific items of equipment to specific test results stored, results of previous tests (e.g., to allow comparison of replaced and replacement components) and the like.
2. Summary of the Invention
The objects of the invention mentioned specifically above, and others appearing as the discussion below proceeds, are met by the present invention, wherein a base unit and one of a selection of application modules, neither being capable of performing enduser functions without the other, are physically assembled to one another to form a structurally unitary device specialized for performance of various application-specific end-user functions.
It is highly desirable that such a device be self-explanatory to a user insofar as possible, so that a user can use the instrument (with differing application modules as needed) to perform such processes with respect to a variety of differing equipment without extensive specialized training.
The base unit is in effect generic to all types of test to be provided, and comprises a display, a power supply, a user interface, and generic software to operate the display and user interface. Each application module is connected to the base unit in the same manner, so that the same base unit can be employed with a wide variety of application modules. The application modules can be readily and conveniently removed from and assembled to the base unit.
The application-specific application modules each include a physical interface for establishing signal-communicating connection to the equipment to be tested, and application-specific program data and software, including information required to provide appropriate test signals, test messages, and the like. Each application module also stores user interface software for providing an application-specific user interface operating in conjunction with the generic display software comprised by the base unit to provide an application-specific user interface, operating in a highly intuitive fashion, e.g., prompting the user to make appropriate selections and input required data to carry out the selected tests.
When an application module is assembled to a base unit, polling software comprised by the base unit determines the identity of the application module, and determines whether it stores any software or other program data not previously copied to the base unit""s memory; if not, the copying step is begun automatically upon assembly. Accordingly, the user need take no significant steps to cause an application module and base unit, after assembly to one another, to establish communication therebetween, further simplifying use of the instrument, and reducing the user training required.
Preferably, the base unit includes a power supply for both itself and the application module, and the application module stores program data and software in nonvolatile memory. Where the power supply includes a battery, a battery monitor circuit provides a low power indication when appropriate, so that the application module can latch the contents of its active registers before the data is lost.